Apparatus for assembling a workpiece

ABSTRACT

AN APPARATUS FOR ASSEMBLING A WORKPIECE, ESPECIALLY A MODULAR WORKPIECE, WHEREIN A GROUP OF ELEMENTS OF THE WORKPIECE IS ORIENTED IN PREDETERMINED ANGULAR AND SPACED RELATIONSHIP IN ONE LOCATION, WHEREIN THESE ELEMENTS, WITH THEIR ANGULAR AND SPACED RELATIONSHIP UNDER CNTROL, ARE TRANSFERRED AS A GROUP TO ANOTHER LOCATION WHERE THEY ARE ASSEMBLED IN SAID PREDETERMINED RELATIONSHIP WITH ANOTHER ELEMENT OF THE WORKPIECE? AND WHEREIN THE ASSEMBLED ELEMENTS ARE INTERCONNECTED.

- 1971 J. E. POWERS ETAL 3,

APPARATUS FOR ASSEHBLING A WORKPIECE Original Filed March 27. 1967 16Sheets-Sheet 1 N lnfir m SN 0: m T w v o m WPB Er H m Z ER SF 0L J AATTORNEY D. 7, 1-971 E POWERS mL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 27, 1967 16Sheets-Sheet I JOSEPH E. POWERS ALFRED F. BASTIAN ATTORNEY Dec. 7, 1971POWERS EI'AL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 2'7, 196'? 16Sheets-Sheet :5

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JOSEPH E. POWERS ALFRED F. BASTIAN M /ZZ4W/ ATTORNEY INVENTORS 7, 1971J, POWERS ETAL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 27, 1967 16Sheets-Sheet L INVENTORS JOSEPH E. POWERS ALFRED F. BASTIAN ATTORNEYDec. 7, 1971 5 POWERS ETAL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 27, 1967 16Sheets-Sheet 5 l INVENTORfi JOSEPH E. POWERS ALFRED F. BASTIAN ATTORNEYJ. E. POWERS ETAL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 2'7. 1967 16Sheets-Shoat 6 NON m we P & H P E s o v ALFRED F. ASTIAN ATTORNEY Dec.7, 1971 POWERS EI'AL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 27, 1967 16Sheets-Sheet v r l 1 '1' I I (D II Q :8 t0 1| [0 IHIIIHIIH'I 1.

INVENTORS JOSEPH E. POWERS ALFRED E BASTIAN ATTORNEY 16 Sheets-Sheet 8 m\J U R m YQ Om m W N I v f "TI lllmllrl l1 0" 1M 1M L r M1 lH r 1 m? MmJOSEPH 5. POWERS ALFRED F. BASTIAN ATTORNEY 1971 J. E. POWERS ETALAPPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 27. 1967 7,1971 POWERS E'TAL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 27, 1967 16Sheets-Sheet 9 INVFL'NTUR, JOSEPH E. POWERS ALFRED F. BASTIAN ATTORNEYwww Llwww 7, 1971 J. POWERS ETAL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 27. 1967 16Sheets-Sheet 10 lNVl-INTOR. aosapu emowsns ALF o F. BASTIAN ATTORNEYAPPARATUS FOR ASSEIBLING A WORKPIECE Original Filed March 27. 1967 16Sheets-Sheet 11 INVENTORS JOSEPH E. POWER ALFRED F. BASTIAN 7, 1971 pows ETAL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 2'7. 1967 16Sheets-Sheet ll ATTORNEY Dec. 7, 1971 J POWERS ETAL 3,624,886

APPARATUS FOR ASSEMBLING A WORKPIECE Original Filed March 27, 1967 16Sheets-Sheet 14.

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APPARATUS, FOR ASSEIIBLING A woaxrmcm Original Filed Marc h 27.1967

16 Sheets-She a I 1 mvsw'rons Jose?" 5. ravens ALFRED F. usmm ATTORNEYDEC. 7, 1971 POWERS ETAL 3,624,886

APPARATUS FOR ASSEHBLING A WORKPIECE Original Filed March 27. 1967 16Sheets-Sheet 16 Own INVENTORS F. B IAN JOSEPH E. POWERS ALFRED%/ATTORNEY United States Patent Olfice 3,624,886- Patented Dec. 7, 1971ABSTRACT OF THE DISCLOSURE An apparatus for assembling a workpiece,especially a modular workpiece, wherein a group of elements of theworkpiece is oriented in predetermined angular and spaced relationshipin one location; wherein these elements, with their angular and spacedrelationship under control, are transferred as a group to anotherlocation Where they are assembled in said predetermined relationshipwith another element of the workpiece; and wherein the assembledelements are interconnected.

This application is a division of application Ser. No. 626,111 filedMar. 27, 1967, now US. Patent 3,507,024 granted Apr. 21, 1970.

BACKGROUND OF THE INVENTION The present invention pertains to anapparatus for assembling a workpiece and more particularly to anapparatus for producing modular workpieces by positioning certain partsof each workpiece in predetermined positions against another part of theworkpiece and for holding all the parts together while they are beinginterconnected in assembled relation.

Although the invention has broader utility, it is conveniently describedin connection with the assembly of certain parts of a segment for aliner of a tunnel ring. As used for underground railroads, for example,many such tunnel rings are attached end-to-end to form a long,continuous tunnel, which, as is well known, prevents collapse of thesurrounding earth. Each tunnel ring is usually made of steel andincludes a plurality of arcuate reinforced segments. In turn, eachsegment is composed of an arcuate channel, end plates inserted in andattached to opposite ends of the channel, and T bars inserted in andattached to the channel between the end plates.

In order to constitute a strong modular segment, that is, one which isinterchangeable with other segments and which will fit with severalother segments to make up a complete ring, the end plates and T barsmust be placed in intimate engagement with, and in precise positionsWithin, the channels. Moreover, especially in view of the demand forsuch tunnels, the assembly of such segments must be performed with aminimum of time, labor and expense.

The prior known apparatus for assembling tunnel ring segments are notsuited to mass production of the segment because they depend too much onmanual operations and are therefore relatively slow and subject to humanerror. For example, as disclosed in the Fine et al. US. Pat. No.2,366,961, it has been known manually to place the individual parts(skin plate, side flanges, end plates and T bar) of a tunnel ringsegment in a jig, to

clamp the parts in the jig, and thereafter to rotate the jig (which ismounted on trunnions for such purpose) into various positions of accessfor a welder. It is apparent that such a manual operation is notconducive to producing tunnel ring segments or modules at a fast ratebecause the rate and manner of placing the parts in the jig is dependenton the human operator.

SUMMARY OF THE INVENTION The present invention avoids the shortcomingsof the prior art by providing an apparatus for assembling several partsof a structural member or other workpiece (which is composed of certainauxiliary parts that must be fitted and attached in a predeterminedmanner to a main part) by precisely arranging the auxiliary partsseparately from the main part in the manner in which they willeventually fit the main part, and then by moving the auxiliary parts asa group and with their relative positions and angles under control intofitted relationship with the main part. By following the concepts of thepresent invention, not only can the production rate be vastly increasedbut also the use of cumbersome and expensive jigs can be avoided.Moreover, since each workpiece, i.e., tunnel ring segment herein, is amirror-image of every other workpiece the parts can be fitted togthermore intimately and with greater precision.

Accordingly, it is an object of the present invention to provide anapparatus for assembling several parts of a workpiece by arrangingcertain auxiliary parts of the workpiece in a predetermined manner inone location and then moving the auxiliary parts as a group, whilemaintaining control over their arrangement, into fitted relationshipwith another part of the workpiece.

Another object is to provide an apparatus for assembling the parts of aworkpiece, such as a tunnel ring segment, on a mass production basis.

Another object is to produce segments or modules of uniform constructionand dimensions so that a number of the segments can be interfitted.

Another object is to pick up a plurality of elements which are in acertain relationship to each other, and to move them out of suchrelationship but under such control that they can readily be returned tosaid certain relationship.

Another object is to provide an apparatus which locates one part of asupported workpiece in predetermined posi tion with respect to aplurality of other parts being held by the apparatus.

Another object is to provide an apparatus for holding the separate partsof a tunnel ring segment in assembled relation and for moving theassembly into various positions of convenient access for welders.

Another object is to minimize the time and expense involved in preciselyand intimately interfitting the parts of a tunnel ring segment, or otherworkpiece.

'BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a top plan of an apparatusembodying the principles of the present invention.

FIG. 2 is a longitudinal vertical section taken on line 2-2 in FIG. 1.

FIG. 3 is a transverse vertical section taken at a position indicated byline 3-3 in FIG. 1 with entry and exit conveyors for the apparatusincluded.

FIG. 4 is an end view of a tunnel ring the segments of which can be madeby the apparatus of the present invention.

FIG. 5 is an enlarged plan of one of the segments in the tunnel ring ofFIG. 4.

FIG. 6 is a longitudinal section taken on line 6-6 in FIG. 5.

FIG. 7 is an enlargement of a portion of FIG. 3 showing an assemblyfixture of the subject apparatus in greater detail with conveyorsections of the fixture shown in level positions in full lines and indeclined positions in dash lines.

FIG. 8 is an end elevation of the fixture shown in FIG. 7 in itshorizontal loading and unloading position and with the channel of atunnel ring segment being held therein.

FIG. 9 is also an end elevation of the assembly fixture of FIG. 8 butwith the fixture in one of its tilted positions.

FIG. 10 is a transverse section taken on line 10-10 in FIG. 7 but with atunnel ring segment being held in the fixture.-

FIG. 11 is a transverse vertical section taken at a position indicatedby line 11-11 in FIG. 2 showing a loading jig of the subject apparatusbut with T bars and end plates shown in dash lines in the jig.

FIG. 12 is a top plan of the apparatus shown in FIG. 11 but with partsbroken away and with the T bars and end plates omitted.

FIG. 13 is a vertical section taken on line 13-13 in FIG. 11.

FIG. 14 is an enlargement of a portion of FIG. 3 showing a carrier ofthe subject apparatus partially broken away and with certain hiddenparts being indicated in dashed lines.

FIG. 15 is an end elevation, partially broken away and showing certainhidden parts in dashed lines, as seen from a position at the right ofthe carrier illustrated in FIG. 14.

FIG. 16 is an enlarged side elevation of an end plate pick-up unit whichis part of the carrier shown in FIG. 14 and showing an end plate held inthe unit.

FIG. 17 is an end view of the pick-up unit shown in FIG. 16 as viewedfrom a position indicated by line 17-17 in FIG. 16 but with the endplate omitted.

' FIG. 18 is a top plan of the pick-up unit shown in FIG. 16.

'FIG. 19 is a top plan of a paddle frame constituting part of the endplate pick-up unit of FIG. 16, although reduced somewhat in scale.

FIG. 20 is a side elevation of the paddle frame shown in FIG. 19.

FIG. 21 is an end view of the frame shown in FIGS. 19 and 20.

FIG. 22 is a side elevation of a clamp frame constituting a part of theend plate pick-up unit shown in FIG. 16, although reduced somewhat inscale.

FIG. 23 is an end view of the clamp frame shown in FIG. 22.

FIG. 24 is a top plan of the clamp frame shown in FIG. 22.

FIG. 25 is an enlarged side elevation of a T bar pickup unitconstituting a part of the carrier shown in FIG. 14 and with a T barbeing shown held by the unit.

FIG. 26 is a view taken on line 26-26 in FIG. 25.

DETAILED DESCRIPTION With particular reference to FIGS. 1, 2 and 3, anapparatus embodying the present invention includes a main frame 30, aloading jig 32 mounted in the main frame at a loading station 34, firstand second assembly fixtures 36 and 38 mounted in the frame at first andsecond assembly stations 40 and 42, in spaced relation to each other onopposite sides of the loading jig, and a carrier 44 mounted on the framefor movement between a loading position, not shown, over the loading jigand releasing positions located alternately over the first and secondassembly fixtures, one of the latter positions heing illustrated inFIGS. 1, 2 and 3. As mentioned above, the method and apparatus of thepresent invention are particularly suited for assembling parts of aworkpiece such as a tunnel ring segment 50 as illustrated in FIGS. 5 and6, and before describing the details of the jig, fixture and carrier,reference is made to this segment.

A plurality of these arcuate segments or modules 50 are interconnectedin a tunnel ring 52, as shown in FIG. 4. The tunnel ring is circular sothat the radii of curvature of the segments intersect in the center ofthe ring. Each tunnel ring segment (or main part or piece as hereinaftersometimes referred to) includes an elongated arcuate channel 56, a pairof rectangular end plates 58, and a plurality of T bars 60 (the endplates and the T bars being some times referred to as reinforcing orauxiliary parts or pieces). The channel has a pair of spaced parallelside flanges 62 welded to opposite side edges of a skin plate 64 whoseconcave inner surface 65 has a predetermined radius of curvature. Thereference to various parts as being either inner or outer is withrespect to the center of the tunnel ring, this center being regarded asthe innermost part of the ring. Each end plate has an outer edge 68intimately engaging the inner surface of the skin plate, a pair of sideedges intimately engaging the inside surfaces of the side flanges, andan inner edge 72 generally in same plane as the inner edges of the sideflanges. Each T bar has a stem plate 76, which has an outer edge 78intimately engaging the inner surface of the skin plate and side edges80 in intimate engagement with the inside surfaces of the side flanges,and a flange plate 82 perpendicular to its respective stem plate andlikewise engaging the inside surfaces of the side flanges, it beingnoted that the flange plate of the T bar is spaced somewhat outward,along the radius of the tunnel'ring, from the inner edges of the sideflanges.

As disclosed herein, the main task of the subject method and apparatusis to assemble the channel 56, the end plates 58 and T bars 60 into atunnel ring segment 50, since all of these parts are initially separatefrom each other. Briefly stated, this task is accomplished as follows:the channel 56 is positioned on one of the assembly fixtures, as 36 andthe end plates 58 and T bars 60 are initially placed in the loading jig32. The carrier 44 picks up the end plates and T bars from the loadingjig, in the same orientation as they were in the jig, transfers themfrom the jig to the assembly station 40 or 42 where the channel islocated, orients the channel relative to the plates and bars, insertsthe latter in the channel in said orientation, and once they are held inthe channel by the assembly fixture, releases them and returns to theloading station 34 to repeat the cycle of operation with the alternateassembly fixture 38. The assembled channel, end plates and T bars areheld together in the assembly fixture until they are at leasttemporarily secured together, as by welding, and thereafter theinterconnected channel, plates and T bars (which may he thought of as apackage) are discharged from the apparatus as a tunnel ring segment(although additional welding and machining are required).

Main frame In more detail, the main frame 30 is positioned on afoundation (FIG. 3) providing a horizontal slab 92 and a verticalperipheral wall 94. The main frame includes a base 98, lowerlongitudinal I-beams embedded in the slab and extending lengthwise ofthe apparatus, pairs of transversely extending I-beams 102, opposedpairs of columns 106, 108, 110, and upper longitudinal I-beams 112connected to the columns on each side of the main frame. Further, tracks116 (FIG. 3) are supported on and secured to the upper I-beams 112.Latch plates 118 are mounted on the upper I-beams, on the insidesurfaces thereof, between each pair of columns and each latch plate hasan inwardly opening socket 120. In addition, a

pair of stop plates 122 project inward from each upper I- beamrespectively adajcent to the columns and slightly below the latchplates. All of the latch plates are in a common horizontal plane and allof the stop plates are likewise in a common horizontal plane which isslightly below the plane of the latch plates.

Assembly fixtures The assembly fixtures 36 and 38 at the assemblystations 40 and 42 are identical and thus only one (i.e. 36) will bedescribed in detail with the same reference numerals being applied tothe same parts on each fixture. The assembly fixture is provided tosupport the channels 56 while the end plates 58 and T bars 60 are beinginserted therein and to hold the channel, the plates and T bars inassembled relation while they are being at least temporarilyinterconnected, as by tack welding. The assembly fixture (FIGS. 7, 8, 9,includes a pair of standards 130 secured to the main frame 30 with eachstandard having a pair of upwardly opening notches 132 therein, it beingnoted that each notch in each standard is in horizontal alignment with anotch in the other standard. The assembly fixture also has U-shaped boxframe 134 which includes a central beam 136 and a pair of legs 138projecting from the central beam and terminating in spaced support arms140. Stub shafts 142 project endwardly from each leg and individuallypivotally rest in the notches of the standards.

The assembly fixture 36 also includes a plurality of C frames 146 havingcentral portions 148 rigidly connected to the U frame 134 andindividually located in radial planes which intersect in a common axis Aabove the assembly fixture, as is viewed in FIG. 3. It will be notedthat the C frames are substantially equally spaced lengthwise of thecentral beam 136, and in the disclosed embodiment, there is a central Cframe, an inside pair of C frames on opposite sides of the central Cframe and in slight angular relation thereto and an outside pair of Cframes spaced outward from the first pair and at a still greater anglewith respect to the central C frame. Each C frame also has a pair oflegs 150 (FIGS. 8, 10) a central ledge 152, a pair of side ledges 154,and notches 156 between the ledges. Blocks 158 are secured to the ledgesand are in a common plane with respect to their individual C frame.Insofar as the blocks on all of the C frames are concerned, they aregenerally tangent to a curved surface having as its center the axis Areferred to above.

A clamp 164 (FIG. 10) is associated with each C frame 146. Each clampincludes a pad 166 mounted on one of the legs 150 of each C frame abovethe adjacent block 158 and adjustable toward and away from the center ofthe C frame and a cylinder 168 mounted on the opposite leg of such Cframe and including a piston rod 170 axially aligned with its associatedpad and movable toward and away from the same upon actuation of itsrespective cylinder. The C frames are intended to support the channels56 with skin plate 64 resting on the blocks 158 on all of the frames andwith the piston rods 170 engaging one of the side flanges and pressingthe other side flanges against the pads 166, as illustrated in FIGS. 8,9 and 10.

The assembly fixture 36 also includes cradling conveyer sections 176each including a rectangular frame 178 having opposite ends 180 andopposite sides 182 and a plurality of rollers 184 journalled in andextending between the sides of the frame. The conveyer sections arepivotally supported in opposite ends of the U frame 134 by pivot pins186 (FIGS. 7 and 8) which project from the legs 138 into opposite sides182 of the frame. The conveyer sections are thus pivoted for movementbetween substantially coplanar positions (also horizontal when the Uframe 134 is positioned with its legs 138 projecting upward as. in FIG.7), as shown in full lines in FIG. 7, and obtusely angulated positions(also declined when the legs 138 project up), as shown in dashed linesin FIG. 7. In the angulated positions of the conveyer sections, thesides 182 of the frames 17 8 are received in the notches 156 of those Cframes 146 that are on opposite sides of the central C frame; for thispurpose, it is to be noted that two relatively large gaps are providedbetween certain rollers 184 to permit each conveyer section to fitwithin the notches and to avoid interference between the rollers and thecentral blocks 158. When the U frame has its legs 138 pointing upwardand when the conveyer sections are in their coplanar positions, theconveyer sections can support a channel 156 with its arcuate skin plate64 resting on the rollers; when the U frame legs point upward and theconveyer sections are pivoted into their angulated positions, theyconstitute a cradle along which the channel can move by gravity (or bemoved by an outside force) for the purpose of bringing the axis ofcurvature of the channel into coincidence with axis A. In theirlowermost angulated positions, the sections lower the channel so thatits skin plate rests on the blocks 158 and its side flanges 62 arebetween the pads 166 and the piston rods of the clamps 164. As anadditional feature, the blocks 158 can include adjustable wedge pieces,not shown, to wedge the blocks tightly against the skin plate.

For pivoting the conveyer sections 176 between their coplanar andangulated positions, cradling cylinders 190 are pivoted within thecentral beam 136 of the U frame 134 and project upwardly throughopenings in the beam and have piston rods 192 pivoted to mounting pieces194 on the frames 17 8 of the conveyer sections. When the cylinders areextended, they support the conveyer sections in coplanar positions andwhen they are retracted they move the conveyer sections in theirangulated positions.

It should be noted at this point that the channels 56 are fed into theassembly fixtures 36 and 38 on respective entry conveyers 195, and theyare removed from the assembly fixtures on exit conveyers 196, the exitand entry conveyers as well as associated assembly fixture in itsupright position defining a conveying path along which the channel andsegment 50 are moved. Also in FIG. 1, a conveyer 198 is shown forconveniently moving the end plates and T bars into a position adjacentto the loading jig 32.

The assembly fixture 36 is intended to be pivoted about the stub shafts142 and for this purpose posts 200 are provided on the main frame 30inwardly (FIG. 3) of the columns 106, it being noted that each pair ofposts is spaced apart (FIG. 8) by about the width of the assemblyfixture as measured by the width of one of the C frames 1*46. Tiltingcylinders 202 have lower ends connected to the posts by pivot pins 204and have piston rods 206 individually connected to the stub shafts 142by collars 208. When both of the stub shafts 142 are in their respectivenotches 156 and the legs 138 and 150 of the U and C frames 134 and 146are pointing generally upward, the assembly fixture is in a conveyingposition. By expanding one set of tilting cylinders, on one side (asdistinguished from the ends) of the assembly fixture, the fixture istilted into a work position (FIG. 9) wherein the legs 138 and 150 aredirected outward in a generally horizontal direction; the assemblyfixture can be returned to its conveying position by retracting this setof cylinders. By expanding the other set of cylinders, the assemblyfixture can be tilted into another work position with the legs pointingoutward on the opposite side from that shown in FIG. 9. The advantagesof this arrangement are the stability of the assembly fixture when it isin a conveying position because the four stub shafts rest in fournotches at the ends of the fixture and the accessibility to workmen,such as welders, of the assembled segment 50 when the assembly fixtureis tilted into one of its two work positions.

Loading jig In order to locate the end plates 58 and T bars 60 inpositions they will eventually assume within a channel 56, the loadingjig 32 (FIGS. 11, 12 and 13) includes a pair of upstanding posts 230mounted on I-beams 232 which extend between the pair of transverseI-beams 102 at the loading station 34. Cross-pieces 234 are secured tothe tops of the posts, and a pair of spaced parallel vertical mountingwalls 238 are secured on opposite sides of the crosspieces and projectupward therefrom. The mounting walls have upper edges 240, each having aseries of fiat portions 242, and intermediate and end openings in theflat portions. With reference to FIG. 11, intermediate, right end, andleft end inserts 248, 250 and 252 are positioned in the openings of theupper edges 240 and are secured to the mounting wall. As used herein,the terms left and right are merely convenient designations fordescribing the apparatus as shown in the drawings and as such have nolimiting effect on the invention. The intermediate inserts have U-shapedslots 254 therein and the end inserts have L-shaped open slots 256therein, it being noted, with reference to both walls 238, that thereare opposed pairs of horizontally aligned slots. The left end andintermediate inserts are adjustable for making different sizes ofsegments 50, but the right end insert is stationary. It is also to benoted that the slots are located in radial planes whiuh intersect inaxis A (above and off the sheet in FIG. 11). Both the angularrelationship and spacing of the slots in the loading jig 32 are the sameas the angular relationship and spacing of the C-shaped frames 146 ofthe a-sembly fixture 36 (and 38 as is believed understood). This angularrelationship and spacing correspond to the desired manner in which theend plates 58 and T bars 60 are to fit within a channel '56, and thusthe slots 254 and 256 respectively releasably receive a plurality of Tbars and end plates; in the disclosed embodiment, the loading jig isconstructed to receive three T bars and two end plates with the stemplates 76 of the T bars and the entire end plates disposed in therespective radial planes if the slot-s. As illustrated in FIG. 1, theslots 254 and 256 of the load ing jig 32 are preferably individuallyaligned longitudinally of the main frame 30 with corresponding C frames146 of the assembly fixtures 36 and 38.

The loading jig 32 also includes an auxiliary wall 260' (FIGS. 12 and13) supported on one of the mounting walls 238 in spaced parallelrelation thereto by brackets 262 and having an upper edge 264 which ishigher than the upper edges 240 of the mounting walls. Adjustable stops266 are mounted in the auxiliary wall in individual alignment with thepairs of aligned slots 254, 256. The ends of the end plates 58 and Tbars 60 engage the adjacent stops 266 when the end plates and T bar aredisposed in the slots thereby correctly to locate the end plates and Tbars transversely of the loading jig. These stops 266 can be adjusted soas to be spaced closer to or farther from the mounting walls.

Carrier The carrier 44 (FIGS. 1, 3 and 14 through 26) includes severalsignificant features of the present invention. The carrier is providedwith a frame 280 having a pair of vertical side walls 282 each of whichhas an intermediate portion 284 and a pair of end portions 286, thelatter being interconnected by vertical end walls 288. Box-shaped trucks292 are secured to and extend between adjacent end portions 286 of theside walls and project endwardly beyond the end walls 288. Withparticular reference to FIGS. 1 and 14, axles 294 are journalled in thetrucks, and wheels 296 on the axles ride on the tracks 116 and therebysupport the carrier for movement lengthwise of the main frame 30 intopositions over the loading jig 32 and the assembly fixtures 36 and 38 atthe loading and assembling stations 34, 40 and 42.

For driving the carrier 44 along the tracks 116, a connecting rod 300 isjournalled in the frame 280, extends between the trucks 292, and isconnected by couplings 302 to an axle 294 in each truck. A motor 306 ismounted on one of the trucks and is connected by a drive linkage,generally indicated by the number 308, to one of the axles thereby torotate the connecting rod and the axle in the other truck. Thus, byenergizing the motor, the carrier is propelled in either direction alongthe tracks.

In order precisely to locate the carrier 44 in the loading andassembling stations 34, 40 or 42, latching cylinders 310 are mounted onthe end walls 288 of the frame 280 and provide latching rods 312 movableendwardly of the frame into and out of the adjacent sockets of the latchplates 118 when the carrier is properly positioned in any one of thestations, as illustrated in FIG. 14. When the latching rods are withinthe sockets, the carrier is locked against movement lengthwise of themain frame 30'. In addition, an L-shaped limit block 320 is secured toeach end wall 288 and includes a horizontal flange 322 which ispositionable under the adjacent stop plates 122 when the carrier islatched in any of the stations. This limit block also includes avertical flange 324 which confronts the vertical edges of the stopplates when the carrier is latched as described. The relationship'between the limit blocks and their associated stop plates is such as tolimit upward movement of the carrier as well as movement of the carriertransversely of the main frame. Fluid power for the latching cylindersis obtained from a power unit 330 mounted on top of the carrier frame280.

With particular attention being directed to FIGS. 3 and 14, it will benoted that the carrier 44 includes a plurality of T bars, pick-up units340, 342 and 344 and a pair of end plate pick-up units 346 and 348,those units being mounted in the carrier frame 280 and individuallydisposed along generally radial planes. When the carrier is located ineither assembly station 40 or 42, the radial planes CTl, GT2, and GT3 ofthe T bar units are the same as the radial planes in which the centraland inside C frames 146 are located, and when the carrier is located inthe loading station 34, the T bar radial planes are the same as theplanes in which the slots 254 are located. The end plate units aretransversely adjustable into and out of similar coplanar relationshipwith the outside C frames and outside or end plate slots 256.

Each end plate pick-up unit as 346 (FIGS. 14, 16, 17, and 18) includes arectangular mounting frame 356 having a pair of spaced parallel sides358 provided with inwardly opening grooves 359, a forward end 360 and arearward end 362. Adjustable stops 364 are provided in the forward endfor movement inward and outward of the frame. Each end plate pick-upunit as 346 also includes a paddle frame 370 (FIGS. 16 through 21)including a slide plate 372 coplanar with the mounting frame 356 andhaving side edges 374 slidably received in the grooves 359, a front edge376 in spaced parallel relation to the forward end 360 of the mountingframe, and a rear edge 378 in spaced parallel relation to the rear end362 of the mounting frame. The slide plate has a generally U-shapedopening 380 therein with a substantial portion of the opening existingin the forward portion of the plate and portions projecting into therear half of the plate.

With continued reference to the paddle frame 370, a support plate 384 issecured to the slide plate 372 centrally thereof and projects bothupward and downward in right angular relation to the slide plate, itbeing noted that the support plate is disposed transversely of the slideplate. The support plate has a front face 386, a rear face 388, a pairof slots 390 open at the lower edge of the support plate and extendingupward therein above the slide plates (FIGS. 17 and 21), and slideways392 on opposite sides of each slot. The three portions of the sup portplate which project below the slide plate are hereinafter collectivelyreferred to as a paddle 396. To impart rigidity to the support plate,forward and rear gussets 404 and 406 extend between the support plate384 and the slide plate 372, and a front rib 408 extends transverselybetween the front gussets. From what has been described so far, it willbe understood that the paddle frame 370 is movable lengthwise of themounting frame 356 between a workpiece engaging position, with the frontedge 376 of the slide plate relatively close to, and perhaps engaging,

